PROBLEM TO BE SOLVED: To provide a host defense component and an oral antibacterial agent or the like as an application of the component and a peptide which have excellent antibacterial activity derived from rice and inflammation inhibiting activity by endotoxin, and are extremely safe even if the agent is prescribed for a long period of time.SOLUTION: A component for host defense or the like contains any one of protein and peptide in (A) to (C) below which exist in a rice seed as active ingredient. (A) protein that consists of specific amino acid sequence (B) protein that consists of specific amino acid sequence in which one to several pieces of amino acid is deleted, substituted or added in the amino acid sequence and has host defense action and (C) peptide that consists of a part of the protein (A) or (B) and has host defense action.
